Many moons ago in my RAF days, us young 'sprogs' were regularly tested on these types of questions to try and promote lateral thinking. I was thick of course, but remember tales of getting around radio failures. One pilot managed to get a phone patch on HF radio and got a talkdown into Belfast via BT at portishead. Some VOR/DME beacons allow(ed) voice to be recieved over the ident, so listen out. (southampton VOR uses this??). Mobile phones or even the passenger satphone system fitted to some jets, modern day datalinks to company HQ so they can give ATC a call etc etc.